Developers seeking new ways of using space and adding value to stock are increasingly turning their attention to low- to mid-rise retail or mixed-use properties built between 1948 and 2018.

Steven Thomas

Steven Thomas

These properties come under permitted development rights (PDR), which enable upwards extension by up to two storeys over certain commercial or mixed-use properties without applying for planning permission (although prior approval will still be required).

In addition to ensuring a potential property is structurally suitable for a rooftop extension, early consideration should be given to the title to the property in order to establish whether there are any impediments to the landlord developing the roof space.

Proposals for rooftop extension schemes at commercial premises typically involve building flats above commercial or retail space, or on top of existing flats above ground-floor commercial or retail space.

These flats and the commercial areas may well be subject to leases, and the rights contained in those leases are one of the first things a developer needs to consider, as they may present real issues to a proposed development.

Abbey Road by Apex Airspace

Abbey Road by Apex Airspace

The key questions that should be asked are: who owns the roof and the roof space? Are they leased to any of the current tenants? Are there common areas over which rights are granted that would be affected by the proposal?

If the answer to any of these is yes, then the consent of tenants will be required for the works, and engagement will be needed with them at an early stage with the aim of obtaining their agreement.

Even where a lease does contain rights for the landlord to develop, these rights cannot override specific rights granted to the tenants; so again, it is important to negotiate with tenants and to get them on side.

It is also important to check the title of the property for restrictive covenants that could impede development. Even the tenant’s right-to-buy provisions contained in the Landlord and Tenant Act 1987 could be relevant.

Steven Thomas is head of commercial property at O’Neill Patient Solicitors